This invention relates to capacitors, especially wound metallized film capacitors.
The dielectric separating the charged layers of a wound capacitor deteriorates with use, finally breaking down completely, resulting in a localized short and consequent increases in local current density. This condition may lead to catastrophic failure in which the capacitor bursts or catches fire.
To prevent such failures, it is known to incorporate within the capacitor a fusing portion which responds to increases in local current density by disconnecting the failed section of metallized film prior to catastrophic failure.